21320003100 has 288 divisors, whose sum is σ = 69469053696. Its totient is φ = 5002905600.

The previous prime is 21320003099. The next prime is 21320003129. The reversal of 21320003100 is 130002312.

It is a happy number.

It is a super-2 number, since 2×21320003100² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 34553992 + ... + 34554608.

It is an arithmetic number, because the mean of its divisors is an integer number (241211992).

Almost surely, 2^21320003100 is an apocalyptic number.

21320003100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21320003100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34734526848).

21320003100 is an abundant number, since it is smaller than the sum of its proper divisors (48149050596).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21320003100 is a wasteful number, since it uses less digits than its factorization.

21320003100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 965 (or 958 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 12.

Adding to 21320003100 its reverse (130002312), we get a palindrome (21450005412).

The spelling of 21320003100 in words is "twenty-one billion, three hundred twenty million, three thousand, one hundred".